may invoice
Regular verb: invoice - invoiced- invoiced

Affirmation 	
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I may invoice
you may invoice
she may invoice
we may invoice
you may invoice
they may invoice 	I may be invoicing
you may be invoicing
she may be invoicing
we may be invoicing
you may be invoicing
they may be invoicing	I may have invoiced
you may have invoiced
she may have invoiced
we may have invoiced
you may have invoiced
they may have invoiced	I may have been invoicing
you may have been invoicing
she may have been invoicing
we may have been invoicing
you may have been invoicing
they may have been invoicing	

Negation 	
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I mayn't invoice
you mayn't invoice
she mayn't invoice
we mayn't invoice
you mayn't invoice
they mayn't invoice 	I mayn't be invoicing
you mayn't be invoicing
she mayn't be invoicing
we mayn't be invoicing
you mayn't be invoicing
they mayn't be invoicing	I mayn't have invoiced
you mayn't have invoiced
she mayn't have invoiced
we mayn't have invoiced
you mayn't have invoiced
they mayn't have invoiced	I mayn't have been invoicing
you mayn't have been invoicing
she mayn't have been invoicing
we mayn't have been invoicing
you mayn't have been invoicing
they mayn't have been invoicing	

Interrogative form 	
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may I invoice?
may you invoice?
may she invoice?
may we invoice?
may you invoice?
may they invoice? 	may I be invoicing?
may you be invoicing?
may she be invoicing?
may we be invoicing?
may you be invoicing?
may they be invoicing? 	may I have invoiced?
may you have invoiced?
may she have invoiced?
may we have invoiced?
may you have invoiced?
may they have invoiced? 	may I have been invoicing?
may you have been invoicing?
may she have been invoicing?
may we have been invoicing?
may you have been invoicing?
may they have been invoicing? 	

Interro-negative form 	
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mayn't I invoice?
mayn't you invoice?
mayn't she invoice?
mayn't we invoice?
mayn't you invoice?
mayn't they invoice? 	mayn't I be invoicing?
mayn't you be invoicing?
mayn't she be invoicing?
mayn't we be invoicing?
mayn't you be invoicing?
mayn't they be invoicing? 	mayn't I have invoiced?
mayn't you have invoiced?
mayn't she have invoiced?
mayn't we have invoiced?
mayn't you have invoiced?
mayn't they have invoiced? 	mayn't I have been invoicing?
mayn't you have been invoicing?
mayn't she have been invoicing?
mayn't we have been invoicing?
mayn't you have been invoicing?
mayn't they have been invoicing?